Process for rendering hydrophobic fibers containing textile antistatic and the treating composition



United States Patent 3,390,009 PROCESS FOR RENDERING HYDROPHOEIC FI-BERS CONTAINING TEXTILE ANTISTATIC AND THE TREATING COMPOSITION Emery I.Valko, Belmont, Mass., assignor to Standard Chemical Products, Inc.,Hoboken, N.J., a corporation of New Jersey No Drawing. Filed Aug. 21,1964, Ser. No. 391,283 2 laims. (Cl. 117-1395) ABSTRACT OF THEDISCLOSURE This invention relates to a process for rendering syntheticfibers antistatic, which comprises impregnating textile materialscontaining a substantial portion of hydrophobic fibers, to give a totaldry weight add-on of between O.4% and 8% by weight, based on the weightof said textile material, with an aqueous acidic solution of a mixtureof Z-carbamoylethyl derivatives of polyoxyethylene amines and theirN-methylol derivatives, with a polyethylene glycol and an acidiccatalyst, removing the water from said impregnated textile material andheating said dried impregnated textile material to cure the impregnatingmixture. The invention also relates to the impregnating compositions.

Textile materials (fibers, filaments, yarns, fabrics and the like) basedon synthetic polymers, such as polyamides, polyesters, acrylics,modacrylics, polyolefins and the like, exhibit a tendency to accumulateelectrostatic charges when processed or used under ordinary conditions.In order to reduce this bothersome tendency which causes difiicuties inprocessing and is objectionable in use, processes have been proposed tocoat the fiber surface with a suitable polymeric material insolubilizedwith the aid of alkaline catalysts. Most of these prior art processeshave serious shortcomings such as high cost, discoloration during thehigh temperature exposure required for the insolubilization, thenecessity of removing the catalyst by afterwash, and incompatibilitywith other desirable finishing agents.

It is, therefore, an object of this invention to provide a process andcomposition for treating textile materials for rendering themantistatic.

A further object is to provide an antistatic textile composition whichis relatively inexpensive and does not discolor under conditions oftextile processing.

Another object is to provide an antistatic textile composition which iscompatible with other conventional textile treating agents and requiresno afterwash.

These and other objects of my invention will become apparent as thedescription thereof proceeds.

The present invention makes it possible to avoid these shortcomings ofthe prior art and to provide durable antistatic finishes for synthetictextile materials with the aid of acidic or acidic-acting catalysts. Forthis purpose compounds are applied containing at least twocarbamoylethyl groups attached to basic nitrogen atoms in admixture withaldehydes, preferably formaldehyde, together with the catalyst.

The carbamoylethyl compounds can be represented by the general formulasin which R represents a monovalent organic radical, R and R representmonovalent organic radicals or hydrogen atoms and R, a bivalent organicradical. The organic radicals may contain additional carbamoylethylgroups attached to basic nitrogen atoms. Particularly efiicient arecompounds having a polyoxyethylene chain in the organic radicals. Such apolyoxyethylene chain has the formula (C'I-I CH O) wherein n representsa number between 3 and These carbamoylethyl compounds are convenientlyprepared by the addition of acrylamide to primary and secondary aminesof the general formula 1 HN\ and IITH-Ra-NH Formula III Formula IVwherein R R R and R represent the same groups as in the above Formulas Iand II.

The preferred aldehyde is formaldehyde and the preferred catalysts aremagnesium chloride, zinc nitrate, Zinc chloride and alkanolaminehydrochlorides.

Instead of applying formaldehyde and the carbamoylethyl compound asseparate compounds they can be precondensed to form methylol compoundsand applied in this form with a catalyst to be condensed by a curingprocess, that is, by exposure to high temperature, to insolublemethylene compounds.

Since the amide group of the carbamoyl group contains two replaceablehydrogen atoms, each carbamoyl group can add two aldehyde molecules orgroups. It is, however, advantageous to use only one aldehyde group percarbamoyl group. If such a ratio is used and the carbamoylethylcompounds contain only two carbamoylethyl groups in the molecule, thecuring results in the formation of a linear polymer. Such a polymer isin general soluble either in water or in organic solvents or in both. Afinish consisting of such linear polymer would have, in general, lowresistance to water and solvents, and therefore poor fastness tolaundering and dry cleaning. In order to improve the fastnessproperties, it is necessary to produce crosslinked polymers. This isachieved by using compounds containing more than two carbamoylethylgroups in the molecule. In accordance with the laws of polymer science,it is possible to achieve these results also by using mixture ofcompounds containing two carbamoylethyl groups and compounds containingthree or more carbamoylethyl groups. In such mixture the molar ratio ofthe compounds containing only two carbamoylethyl groups must be keptunder a certain limit depending how many carbamoylethyl groups arepresent in the other compounds used. Another method to achievecrosslinking is by use of dialdehyde or polyaldehyde instead offormaldehyde, i.e. glyoxal or glutaraldehyde. Most of the carbamoylethylcompounds and their methylol derivatives are water soluble either inform of the free bases or in form of their salts. Such salts are easilyproduced by neutralizing the free amine groups with such organic acidsas formic, acetic, lactic, glycolic acids or inorganic acids such ashydrochloric or nitric acid.

The textile materials are provided with the required finish in threesteps: (1) impregnation with an aqueous solution containing thereactants and the catalyst, (2) removal of the solvent water and (3)heat-curing. The impregnation can be accomplished by padding followed bysqueezing. The removal of water can be accomplished by evaporation atelevated temperature. The curing can be done by exposure to atemperature of 100 C. to 200 C. The exposure time varies between a fewseconds and a few minutes. The conventional time-temperature relationprevails: the higher the temperature, the shorter is the time requiredto complete the condensation leading to the formation of the insolublepolymer.

I found that in order to obtain an efiicient antistatic finish, thepolymer should preferably contain a chain of oxyethylene (OCH- CHgroups. There are several ways to introduce these groups. For example,as mentioned above, a polyoxyethylene compound containing one or twoamino groups can be used as the primary or secondary amine of FormulasIII and IV. Such a compound is commercially available under the tradename Polyetherdiamine from the Union Carbide Corporation. Polyglycolscontaining reactive chlorine such as obtained by reaction of polyglycolswith thionylchloride or by addition of epichlorohydrin in presence of asuitable catalyst to polyglycols, can be reacted with excess ofpolyamines such as ethylene diamine or diethylenetriamine to obtainmixtures of primary and secondary amines containing suitablepolyoxyethylene chains in the molecule. Furthermore, such compounds canalso be obtained by reacting mixtures of polyglycols and compounds ofFormulas I and II with formaldehyde or with other reactive aldehydes.This reaction can be carried out concurrently with the heat curingprocess.

The amount of finish required to obtain varies with the nature of thetextile material and with the degree of antistatic protection desired.For most purposes a total add-n between 0.4 percent and 8 percent byweight on the weight of the textile appears a suitable amount.

The following specific examples are presented to illustrate theinvention and to enable persons skilled in the art to better understandand practice the invention and are not intended to be limitative.

EXAMPLE I A. Preparation of carbamoylethyl compounds For the preparationof tris(2-carbamoylethyl)amine (Compound I) 24.08 grams (0.34 mole) ofacrylamide were dissolved in 50 grams distilled water. To this solutionwere added 50 grams of 28% NH OH (0.825 mole NH;.,) and the reactionmixture was left standing at room temperature overnight. Afterevaporation of the water at 20 mm. Hg and 65 C., the solution becamevery viscous.

Upon cooling, the mixture solidified to a white crystal. 25.70 grams oftris(2-carbamoylethyl)amine (98%) were obtained. Titration for thepresence of double bond indicated that the reaction had proceeded toover 98% completion.

EXAMPLE II For the preparation of tris(N-methylol-Z-carbamoylethyl)amine(Compound II) 13.60 grams (0.0592 mole) of tris(2-carbamoylethyl)aminewere dissolved in 26 grams distilled water and 14.4 grams 'of 37%formaldehyde solution were mixed with the solution. The solution wasleft standing at room temperature overnight. This ratio of reagents gave3 moles HCHO for each mole of amine. The solution was 35% active oftris(N-methylol-2- carbamoylethyl) amine.

EXAMPLE III For the preparation of tetra(2-carbamoylethyl)ethylenediamine (Compound III) 6.540 grams (0.1 mole) of 92% ethylene diaminewere dissolved in 100 ml. CH OH.

To this solution were added 28.40 grams (0.4 mole) of acrylamide. Thereaction mixture was left standing at room temperature for three days.The product was a white crystal adhering to the bottom of the flask.After recrystallization with acetone, the product was dried under vacuumfor 2 hours. Yield of the reaction was 25.50 grams Analysis for thepresence of double bond indicated the reaction had proceeded over 98% tocompletion.

EXAMPLE IV For the preparation of tetra(Nmethylol-Z-carbamoylethyl)ethylene diamine (Compound IV) 8.80 grams(0.0256 mole) of tetra(2-carboylethyl)ethylene diamine were dissolved in50 grams distilled water. T 0 this solution were added 8.32 grams of 37%formaldehyde solution. This ratio of reagents gave 4 mole HCHO per moleof amine. The solution was left standing at room temperature overnight.The solution was 20.8% active of tetra-(N-methylol-2-carhamoylethyl)ethylene diamine.

EXAMPLE V For the preparation of tetra(2-carba-moylethyl)1,3 diaminopropane (Compound V) 7.413 grams (0.10 mole) of 1,3 diamino propane weredissolved in 100 ml. CH OH. To this solution were added 28.4 grams (0.40mole) of acrylamide. The reaction mixture was left standing at roomtemperature for three days. The solvent was evaporated under vacuum atroom temperature. The product was a white solid which was dried undervacuum for 2 hours. Analysis for the presence of double bond indicatedthe addition reaction had completed over 98%.

EXAMPLE VI For the preparation of tetra(N-rnethylol-Z-carbamoylethyl)l,3diamino propane (Compound VI) 6.45 grams (0.018 mole) oftetra(2-carbamoylethyl)1,3 diamino propane were dissolved in 50 gramsdistilled water. To this solution were added 5.85 grams of 37% HCHOsolution. The solution mixture was left standing at room temperatureovernight. The ratio of reagents gave 4.0 mole HCHO per mole of amine.The solution was 13.5% active of tetra(N-methylol-Z-carbamoylethyl)1,3diamino propane.

EXAMPLE VII For the preparation of penta(Z-carbamoylethyl) imino bispropylamine (Compound VII) 13.123 grams (0.10 mole) ofimino-bis-propylamine were dissolved in 100 ml. CH OH. To this slightlyexothermic mixture were added slowly 35.5 grams (0.5 mole) ofacrylamide. The reaction mixture was left standing at room temperaturefor three days. After evaporation of the CH OH under vacuum at roomtemperature, the product was viscous pale yellow liquid. Titration ofthe double bond indicated the reaction had proceeded over 98%.

EXAMPLE VIII For the preparation ofpenta(N-methylol-Z-carbamoylethyl)imino bis propylamine (Compound VIII)38.88 grams (0.08 mole) of penta(Z-carbamoylethyl)imino bis propylaminewere placed into 32.5 grams of 37% HCHO solution. The high viscosity ofpenta(2-carbamoylethyl) imino bis propylamine delayed the formation of ahomogenous solution upon stirring. The mixture became homogenous after 3days. The product was 66.5% active of penta(N-methylol 2carbamolyethyl)imino bis propylamine.

EXAMPLE IX For the preparation of penta(Z-carbamoylethyl)bishexamethylenetriarnine (Compound IX) 43.0 grams (0.2 mole) of bishexamethylenetriamine were dissolved in 250 ml. CH OH with somestirring. To this solution were added 71.0 grams (1.0 mole) ofacrylamine. Again some stirring was required to form a homogenoussolution. The reaction mixture was left standing over a week. After thesolvent was stripped off under vacuum at room temperature, analysis ofthe presence of double bond indicated over 98% of addition hadcompleted.

EXAMPLE X For the preparation of penta(N-methylol-Z-carbamoylethyl)bishexamethylene triamine (Compound X) 57.04 grams (0.1 mole) ofpenta(2-carbamoylethyl)bis hexamethylenetriamine were dissolved in 40.5grams of 37% HCHO solution. Only after three days the solution becamehomogenous. The product was 73.6% active of penta(N-methylol 2carbamoylethyl)bis hexamethylene triamine.

EXAMPLE XI For the preparation of tetra(2-carbamoylethyl)1,4-cyclohexane bis(methylamine) (Compound XI) 14.2 grams (0.10 mole) of 1,4cyclohexane bis(methylamine) were dissolved in 100 ml. CH OH. Thereaction mixture was left standing for three days. The product, afterthe solvent was driven off under vacuum at room temperature, was notsoluble in water.

EXAMPLE XII For the preparation of tetra(N-methylol-2-carbamoylethyl)l,4cyclohexane bis(methylamine) (Compound XII) 26.92 grams (0.0632 mole) oftetra(2-carbamoylethyl)l,4 cyclohexane bis(methylamine) were dissolvedin 100 ml. 0.6 N HCl. To this solution were added 20.5 grams 37 HCHOsolution. This ratio of reagents gave 4 moles HCHO per mole of amine.The product was 23.4% active of tetra(N-rnethylol-Z-carbamoylethyl)1,4cyclohexane bis(methylamine) EXAMPLE XIII For the preparation oftetra(2-carbamoylethy1)polyglycol diamine H221 (Compound XIII) 22.1grams (0.1 mole) of polyglycol diamine H221 were dissolved in 125 ml. CHOH. To this solution were added slowly 28.4 grams (0.4 mole) ofacrylamide. The reaction mixture was left standing for 8 days. Analysisof the presence of double bond indicated over 99% completion of additionhad occurred.

EXAMPLE XIV For the preparation oftetra(N-methylol-2-carbamoylethyl)polyglycol diamine H221 (Compound XIV)25.25 grams (0.05 mole) of tetra(2-carbamoylethy1)polyglycol diamineH221 were dissolved in 32.60 grams of 37% HCHO solution. This ratio ofreagents gave 4 moles HCHO per mole of diamine. The product was 65.2%active of tetra(N-methylol-2-carbamoylethyl)polyglycol diamine H221.

EXAMPLE XV For the preparation of tetra(2-carbamoylethyl)polyetherdiamine L1000 (Compound XV) 100 grams (0.1 mole) of polyether diamineL1000 were dissolved in 200 ml. CH OH. To this solution were added 28.4grams (0.4 mole) of acrylamide. The reaction mixture was left standingfor three days. After the solvent was stripped off under vacuum,analysis of the presence of the double bond indicated 98% reaction hadcompleted.

EXAMPLE XVI For the preparation oftetra(N-methylol-Z-carbamoylethyl)polyether diamine Ll-000 (CompoundXVI) 119.5 grams (0.093 mole) of tetra(2-carbamoylethy1)polyetherdiamine L1000 were mixed with 30.40 grams of 37% HCHO solution. Theratio of reagents gave 4 moles I-ICHO per mole diamine. The product was82.5% active of tetra(N-methylol-Z-carbamoylethyl)polyether diamineLl000.

EXAMPLE XVII For the preparation of tetra(2-carbamoylethyl)polyetherdiamine L2000 (Compound XVII) 200 grams (0.1 mole) of polyether diamineL2000 were dissolved in 500 EXAMPLE XVIII For the preparation oftetra(N-methylol-Z-carbamoylethyl) polyether diamine L2000 (CompoundXVIII) 178.70 grams (0.078'2 mole) of tetra(2-carbamoylethyl) polyetherdiamine L2000 were mixed with 25.40 grams of 37% I-ICHO solution. Thisratio gave 4 moles HCHO per mole diamine. The product was 92.3% oftetra(N- methylol-2-carbamoylethyl) polyether diamine L2000.

B. Preparation of impregnating liquor The above listed compounds wereused in the preparation of the solutions for impregnation of fabrics.Three sets of experiments were carried out.

In the first set Polyethylene Glycol 600 (a commercial brand of thecompound HO(CH CH O H of the average molecular weight 600) and one ofthe methylol compounds were dissolved in water. The molar ratio of thesecompounds was 0.88 mole Compound II, 0.66 mole Compound IV, 0.66 moleCompound VI, 0.53 mole Compound VIH, 0.53 mole Compound X, 0.66 moleCompound XII, 0.66 mole Compound XIV, 0.66 mole Compound XVI and 0.66mole Compound XVIII to 1 mole Polyethylene Glycol 600.

In the second set each of 0.75 mole Compound XIV, 0.75 mole Compound XVIor 1 mole Compound XVIII was mixed with 1 mole of Compound I.

In the third set the following pairs of compounds were dissolved inequimolar quantities: Compound III and Compound IV; Compound V andCompound VI; and Compound III and Compound VI; Compound V and CompoundIV.

The aqueous solutions were diluted to contain 12.5 grams of solidsconsisting of the above mixtures in 100 ml. The solution was adjusted toa pH value of 2 to 2.5 by addition of dilute hydrochloric acid. Inaddition, the catalyst, 4 to 15 grams of MgCl .6H 'O per 100 ml.solution was added.

C. Impregnation and drying of fabric In each of the above describedsolutions, a plain weave, desized Dacron polyester fabric, using aseparate piece for each of the solutions, was saturated by immersing itinto the solution and leading it between rolls of a laboratory puddingmachine. It was found that the fabric had retained approximately 40percent of its own weight of solution containing aproximately 5 percentfinishing compounds on the weight of the fabric. The fabric pieces weredried for 7 minutes in an oven at to C.

D. Heat curing The dried fabric pieces were placed in a hot-air oven ofto C. and kept there for 5 minutes.

E. Behavior of the finished fabric After removal of the unreacted finishand the catalyst by rinsing with water, the fabrics were investigatedfor their tendency to accumulate electrostatic changes. Whereas theunfinished fabric attracted cigarette ash if rubbed against worstedfabric and then rapidly placed at a height of 0.5 inch over the ash, allof the treated fabrics remained free of ash if tested identically. Foraquantitative test, the electrical resistance values of the fabrics weredetermined. It is known that electrical charges are dissipated rapidlyif the surface area resistivity (SAR) is below 10 ohms (log SAR 12).Whereas the untreated fabric has shown a surface area resistivity higherthan 10 ohms, the finished fabrics have surface area resistivities below10 ohms. Specifically, the results were as shown in Tables I, II andIII.

7 TABLE 1 (Set I) Polyethylene Glycol 600 and Examples: Log SAR XIXCompound II 9.3 XX, Compound IV 8.6 XXI, Compound VI 9.0 XXII, CompoundVIII 8.6 XXIII, Compound X 8.6 XXIV, Compound XII 9.4 XXV, Compound XIV8.5 XXVI, Compound XVI 8.4 XXVII, Compound XVIII 8.6

TABLE II (Set II) Examples: Log SAR XXVIII, Compound I with Compound XIV9.9 XXD(, Compound I with Compound XVI 10.1 XXX, Compound I withCompound XVIII 9.8

TABLE III (Set III) Examples: Log SAR XXXI, Compound III with CompoundIV 10.1 XXXII, Compound V with Compound VI 10.6

XXXIII, Compound III with Compound VI 10.5 XXXIV, Compound V withCompound IV 11.4

It is to be noted that the finishes of Set III while still possessingantistatic properties are less efficient than the finishes of the firsttwo sets, which contain polyoxyethylene chains.

Further tests which were conducted 'have shown that the antistaticprotection was maintained after several washings and dry cleanings.

Although the above examples are carried out with a woven fabric, textilematerials in other form, such as fiber, filaments, tow, yarn, knittedfabric as well as non-woven structures, flocked and Itufted fabrics canbe likewise treated.

In addition to hydrophobic textile materials made of synthetic fiberssuch as nylon, polyester, cellulose triacetate, acrylics, modacrylics,polyvinylchloride, polyolefins, those made of wool have also tendency toaccumulate electrostatic oharges and therefore need antistatic finsh.Blends made of hydrophobic fibers and hydrophilic fibers, such as rayonand cotton likewise require antistatic protection if the ratio of thehydrophobic fibers is substantial.

In order to increase the antistatic efficiency, the amine groups of thecarbamoylethyl compounds can be partially or completely converted intoquaternary ammonium compounds. For this purpose, the carbamoylethylcomplied as free bases in order to maintain their reactivity towards thealkylating agents.

The antistatic finish described can be combined with other finishingagents. Particularly convenient is the com- 'bination with otherfinishes based on nitrogenous resins (urea/formaldehyde,melamine/formaldehyde and the like). These finishes require catalystsand heat-curing of the same kind as the antistatic finish and thereforecan be applied simultaneously with it, making additional stepssuperfluous. Particularly desirable are such combinations in thefinishing of textile materials of blends. Softeners, lubricants, waterrepellents, stain repellents, anti-bacterial agents, dyes and pigmentscan be like-wise combined with the antistatic finish.

While certain specific examples and preferred modes of practice of theinvention have been set forth it will be understood that this is solelyfor the purpose of illustration and that various changes andmodifications may be made without departing from the spirit of thedisclosure and the scope of the appended claims.

I claim:

1. A process of reducing the tendency of textile materials containing asubstantial portion of hydrophobic fibers to accumulate electrostaticcharges which comprises impregnating said textile material, to give atotal dry weight add-on of between 0.4% and 8% by weight based on theweight of said textile material, with an aqueous acidic solution of -(A)a mixture of Z-carbamoylethyl compounds and their N-methylol derivativesselected from the group consisting of (1) 0.75 mole to 1 mole of awater-soluble compound of the formula CH --CH CONHCH OH 2 where R, is abivalent organic radical containing a polyoxyethylene chain of theformula (CH CH O) where n is an integer from 3 to 80, with about 1 moleof a. water soluble compound of the formulae selected from the groupconsisting of (NI-I COCH CH 3EN and where p is an integer from 2 to 6and R is selected from the group consisting of R and where m is 0, and(2) 0.53 mole to 0.88 mole of a watersoluble compound of the formulaeselected from the group consisting of and pounds are treated withalkylating agents, such as diethylsulfate, dimethylsulfate,elthylbromide, ethylenechlorhydrin, 'benzylchloride or ethyliodide,before or afiter reacted with formaldehyde. Quaternization can also becarried out on the textile materials during or after curing. For thispurpose, it is convenient to use non-volatile watersoluble alkylatingagents, such as polyethyleneglycol diiodide (I(CH CH O) CH CH I) inwhich x is a number between 5 and 40, preferably between 12 and 15.These agents can be dissolved in the impregnating solution containingthe resin forming components and the catalyst. The use of amine catalystin this case must be avoided and the carbamoylethyl compounds notneutralized but apwherein R, R R and m have the above-assigned values,with about 1 mole of a polyethylene glycol having from 3 to oxyethyleneunits, and (B) an acidic catalyst, removing the water from saidimpregnated textile material and exposing said dried, impregnatedtextile material to a temperature between C. and 200 C. for a timesufiicient to cure said mixture.

2. A composition for treating textile materials containing a substantialposition of hydrophobic fibers consisting essentially of an aqueousacidic solution of (A) a mixture of Z-carbamoylethyl compounds and their'N-methylol derivatives selected from the group consisting of (1) 0.75mole to 1 mole of a water-soluble compound soluble compound of theformulae selected from the group of the formula (HO CH NH-COCHz-CH2)2=NR4N=(CHg-CHg-C o-NH-ornoH where R; is a bivalent organicradical containing a polyconsisting of oxyethylene chain of the formula(CH CI-I O) where n wherein R, R R and m have the above-assigned values,is an integer from 3 to 80, with about 1 mole of a water with about 1mole of a polyethylene glycol having from soluble compound of theformulae selected from the 3 to 80 oxyethylene units, and (B) an acidiccatalyst. group consisting of and z-C 0-CH2C 2)2= 1-N=( 2C 2C 0-NH2):CHrCHr-C O-NHgJ where m is an integer from 0 to 1, R is (CH whereReferences Cited p is an integer from 2 to 6 and R is selected from the30 UNITED STATES PATENTS group consisting of R and 2,663,733 12/1953Subluskey 1l7--139.4 X 3,167,384 1/1965 Andrews et a1. 117161 CH3,168,415 2/1965 Goldstein et al. 117-139.4 2 5 35 3,202,473 8/1965Andrews et al. 117-143 Ami-cg CH-CHT" 3,247,018 4/1966 Hagge et a1.117139.5 cm-ofi, 3,258,305 6/1966 Andrews et a1. 117-161 WILLIAM D.MARTIN, Primary Examiner.

when m is 0, and (2) 0.53 mole to 0.88 mole of a water- 40 T. G. DAVIS,Assistant Examiner.

